Guardian Gear - Dog Puppy Martingale Chain Collar - 6 Colors - S, M, L Our Guardian Gear, Martingale Dog Collars combine the convenience of an adjustable collar with added safety and control of a choke-style collar. Collar size adjusts as pressure is applied to the leash Limited closure guarantees that the collar will not injure pets Material: 100% Nylon; Metal chain link To determine the proper size, measure the circumference of pet neck and add 2"5/8 wide (small) Fits necks 13"-18"3/4" wide (medium) Fits necks 16"-24"1" wide (large) Fits necks 22"-34".
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